


Enter: The Fallen Child

by themystery424



Series: I'll Love You Even When You Forget My Name [9]
Category: Undertale, Undertale (Video Game)
Genre: Comfort, M/M, Some Fluff, but at least it's long?, fallen child one enters the scene, fights everywhere, it's an interesting update guys, more plot orientated than grillster related, some agnst, soul fight
Language: English
Status: Completed
Published: 2017-05-26
Updated: 2017-05-26
Packaged: 2018-11-05 01:50:11
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 3,701
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11003478
Author URL: https://archiveofourown.org/users/themystery424/pseuds/themystery424
Summary: After two years of marriage, Gaster is moved to an underground lab to work on making synthetic human souls- a task pretty much impossible without an actual human soul to study. Asgore promises to give Gaster the soul of any human that falls, then proceeds to break that promise. The human discovered their power to reset in an unfortunate way.(OOOOH MAN THIS ONE TOOK FOREVER. FOR. EVER. I'm also pretty proud of it. :) Another update!! Woosh!))





	1. Workplace Hazzards

**Author's Note:**

> Italics are signing.  
> Gaster talking is always in Wingdings.

The lab staff had expanded a lot over the following two years. Gaster liked working alone, all the other scientists were aware of the fact. So, as the lab filled, it became harder and harder for Gaster to work. Eventually the scientist snapped. 

Grillby had been visiting, which was usually relaxing and made Gaster feel at ease. But that day, as scientists bustled around Gaster, reaching around, bumping into him and spilling chemicals, Gaster reached his breaking point. His eyes had disappeared, and blue magic erupted around him. Scientists, lab assistants and Grillby had been knocked back against the walls, bones appearing like spears around the skeleton as a second defense.

“Gaster!” Grillby yelled. “Gaster, stop this now! C’mon!”

Gaster was panting, his smile unnaturally wide and gaping open, panicking. “Grillby?” He called out weakly.

“Yes, Gaster. Now let everyone down, please?”

“I-it’s too many monsters. I can’t…”

Grillby had never known Gaster to have any fears or anxieties, or ever get overwhelmed. The fire monster assumed it  _ could  _ happen, just not to his Gaster, and especially not in a setting like this. 

“They’ll leave.” Grillby bargained. “Let them down slowly, and they’ll leave.” 

Gaster hesitated before slowly letting the scientists and assistants done, who left once they were on the floor. The bones vanished, and soon Grillby was the only one still suspended by blue magic. Gaster’s smile had reverted back to it’s normal size, but was set in a frown. His eyes were still gone as he walked towards Grillby, who was still pinned against the wall.

Grillby took a deep breath. “Wingdings… can you please let me down?” With Gaster right in front of him, the blue magic lost its hold, and Grillby dropped. He landed on his feet, although a little wobbly. Gaster’s eyes finally returned, and Grillby held him in his arms, looking into the pinpricks of white. 

“I-I’m sorry.” Gaster whispered. “I don’t know what came over me.”

“Sh… it’s alright, it’s alright.” Grillby soothed quietly. “It’s okay… have you always been bad with this many people?”

“I’ve never been in this proximity to so many people. Usually my teams are much smaller.” 

The fire monster nodded, stroking Gaster’s skull lightly. 

“Let’s go to the bar, okay? Tomorrow you can explain to Asgore what happened.” Gaster nodded. He let Grillby lift him up, carrying him bridal style to the Riverperson’s boat, and all the way to the bar. Grillby set him down on the floor by the skeleton’s favorite stool. Gaster slid onto it carefully, watching as Grillby ran around behind the bar and grabbed a bottle of ketchup. 

“You’re too good for me, Grillby.” Gaster whispered, taking the bottle. He drank, the bartender watching him worriedly.

“Are you okay, Wingdings?” He asked softly. “I’ve never seen that side of you.”

“Ugh… yeah. There was so much movement, so many bodies, everyone rushing around… It reminded me of… you know.” And Grillby did know. They don’t discuss it, the time before the barrier, the war. Especially if you were part of the unlucky innocents caught in the crossfire. Grillby had a suspicion that, since Gaster was so close with the queen and king and never discussed his birth parents (even when Grillby questioned him), it seemed incredibly likely he was one of those innocents.

Grillby held Gaster tightly. “You know you can talk to me, right?”

“Yes.” Gaster nodded. “I don’t need to, though. I’m fine.”

Grillby rolled his eyes, not believing him. “Screw your courage to the sticking place.” He muttered, and Gaster’s eyes brightened.

“Did you just quote Macbeth?” He asked excitedly, and Grillby chuckled before nodding. “I love Macbeth! It’s my favorite Shakespeare play.” Gaster beamed. Grillby got himself comfortable, smiling contently. When Gaster was ready, he’d say his role in the war, but for now, Grillby would listen to his detailed recount of Macbeth.

 

Gaster hesitated before knocking on the door to the throne room. He wasn’t sure how he was going to go about this. Obviously he couldn’t work in such a confined space. Even before yesterday’s incident, he had made almost no progress on his own projects. Although pointing this out may have adverse effects, like getting innocent, bright-eyed scientists fired. If it came down to it, of course he’d through the discomfort.

The door opened, and as always, Gaster was greeted with a warm smile and two bright, proud eyes.

“Howdy Gaster!” 

Gaster felt nervous all of a sudden, swallowing hard.  _ “Hello sir.”  _ He signed, his hands shaking some.  _ “Did you hear about yesterday?”  _

“Of course I did.” Asgore replied, opening the door for Gaster to come in. The scientist stepped in hesitantly. Then he waited, wondering when Asgore would shout or yell or condemn him for his actions. But the king didn’t. Instead he poured Gaster a cup of tea. “Thirsty?”

_ “I-, yes sir.”  _ Gaster replied. He took the offered cup and sipped, though still waited. Asgore was still smiling, sipping his tea in delight. He noticed the skeleton’s stiff posture and guilty eyes, and sighed.

“Gaster, I’m not mad at you.” He assured him. Gaster’s eyes darted to the king, wide and unbelieving. “It’s true, I’m not. I understand. I remember just as well as you do, the times before the barrier… It was my fault for hiring so many monsters to work by your side. I should have been more considerate.”

_ “No! No, no your majesty, I should have controlled my power better.”  _ Asgore cut him off with a wave of his hand.

“It doesn’t matter, I was going to move you to a different lab all the same. You see, I have… an impossible task to ask of you.” Asgore told him slowly. Gaster’s fear and guilt immediately vanished. He loved puzzles, and loved accomplishing impossible tasks. His eyes glowed a faint purple as he listened to Asgore with interest.

_ “What kind of task?” _

“I want you to try and design a synthetic human soul.” Asgore told him. “Create something that will fool the barrier, make it seem as if the power present is actually real human souls. There’s lab space under the lab you currently work in, but the entrance to it was accidentally blocked off with the construction of the main laboratory. And with your ability to teleport-”

_ “-find shortcuts.”  _ Gaster corrected, making the king chuckle.

“-find shortcuts, yes, I think you could work down there by yourself. You are still able to work on your own projects of course, but with some space from the others. How does that sound?”

Gaster thought, but didn’t think about the offer. His mind was already going to work on trying to create the synthetic souls. His thoughts hit a snag almost immediately, and he frowned.

_ “Asgore, to recreate the structure of a human soul, I would need to dissect one and figure out how it works first. I happily accept the task, though! I would love to work in underground lab space.”  _ Asgore nodded.

“As I said, an impossible task. Which is why you’re free to work on your own tasks down there as well. And if a human ever falls down here, somehow we’ll harvest their soul, and it’s yours to study.”

Gaster cringed at the idea of the king, or any monster for that matter, having to kill a living creature, but at the same time he knew it was what needed to be done.

_ “I look forward to that day, Asgore. On that day, we’ll be one step closer to getting out of this gilded cage.”  _ Asgore, now looking grim, turned away from Gaster. The scientist took that as his cue to leave, but stopped at the door when he heard the king mutter.

“But… at what cost?”


	2. The Child

**Summary for the Chapter:**

> Meeting the Human

Gaster sometimes brought Grillby to the underground lab, the fire monster watching him work from a stool. Though with Grillby there, Gaster hardly got any work done. Which was why it was rare Gaster brought him there at all. Today, Gaster was actually working, with Grillby watching him. He raised an eyebrow at the bunsen burner the scientist was using.

“You know I could burn hotter, faster, and you wouldn’t have to worry about fumes or gas.” Grillby remarked casually, and Gaster laughed.

“I need to be able to control the heat myself, love. Besides the gas and fumes don’t really bother me.” Gaster replied, turning from the burner for a moment to make a few notes. Grillby got up, and Gaster smiled wider, completely expecting it when the arms made of fire wrapped around his middle. He could feel the heat of his husband’s flames against his back. The sensation made Gaster melt back into him, eyes fluttering close.

“I think you can control this flame pretty well.” Grillby whispered.

“If I could, I’d actually be getting some work done now.” Gaster whispered back, and Grillby chuckled, making his chest rumble. The scientist turned around, pulling Grillby in for a kiss. Grillby was sliding his hand under Gaster’s turtleneck when the scientist’s phone went off. Gaster sighed, pulling his phone out. “Hello?” He asked, doing his best to ignore Grillby’s kisses.

“Gaster.” Asgore’s voice came from the other end quickly, not bothering to wait for the translator. “I need you at New Home now. It’s urgent.” Gaster felt a weight drop in his stomach. He hung up and pulled free of Grillby’s embrace.

“We need to go.” He said. 

“What is it? What’s happening?” Grillby, confused and slightly dazed, grabbed their coats. Gaster took his and slid it on over his white turtleneck.

“No idea… but I fear the worst. I fear for Asriel’s safety.” Gaster’s eyes were glowing a dim purple color. He took Grillby’s arm. “Ready?” 

“Always.” Grillby replied, in a tone so soft and heartfelt Gaster almost melted. The two walked forward, towards New Home’s stairs. Grillby, as he always did, looked dumbfounded, and Gaster wondered if the charm using short cuts would wane on Grillby eventually. He hoped not.

Once in front of the stairs, the two bolted up the stairs, running as fast they could. Gaster didn’t bother with knocking, running into New Home.

“Toriel!” Gaster shouted.

“Asriel! Asgore!” Grillby yelled as well.

“In here!” Asriel’s sweet voice brought relief to Gaster, whose eyes returned to the pinpricks of white they’d been before. A little more calmly than before, Gaster and Grillby shuffled to the boy’s bedroom. What they saw stopped them cold, and the purple glow returned to Gaster’s eyes.

A brown haired,  _ human child,  _ was sprawled out on Asriel’s bed. They were wearing a similar sweater to Asriel’s, yellow and green. They looked bruised, beat up and scraped, which Gaster assumed was from the fall. Their eyes were half-lidded, revealing a flash of an unnerving red color.

“I still… don’t understand…” The child coughed.

“Chara, child, save your strength.” Toriel replied, running her hand through their hair. “We’ll explain it to you later.”

“Uncle Gaster and Uncle Grillby!” The prince shouted, and the queen and king turned around, smiles on their faces.

“Oh thank goodness you’re here… Gaster, can you look this child over?” Toriel asked him. Gaster hesitated before he nodded stiffly. Grillby watched with concern, his husband sitting on the bed. The skeleton hesitated before using blue magic to grab the child’s soul. Chara, the name of the child apparently, screeched.

“What are you doing!”

_ “Checking you for damage.”  _ Gaster signed.  _ “Toriel, their HP is low. 3/20. They need nourishment.”  _

“Oh dear!” Toriel lept to her feet. “I’ll make them something at once!” She ran to the kitchen. Gaster let the child’s soul go, showing a brief view of their soul before it disappeared back into their chest completely. Grillby watched, confused at the sight. The soul was pure white, as if it were an unborn monster’s, and it was upside down, the point at the bottom instead of the top. Gaster seemed equally perturbed. The scientist cleared his throat and turned to his husband.

“Grillby-” The child yelped, and Gaster jumped, turning around.

“What was that  _ horrible  _ noise you made!” Chara demanded, scowling.

“Oh that’s just how Uncle Gaster talks.” Asriel explained with a shy smile. Looking at Asriel, Chara’s agitation faded, and they smiled, almost kindly, in response. Grillby noticed it and felt dread creep through his flames. He turned to face his husband head on, ignoring the exchange. Gaster was signing at him.

_ “-watch them while I talk to the king?”  _

“I can do that, of course.” Grillby nodded. Gaster took Asgore by the arm and pulled him into the hall. Grillby returned his attention to the children. Chara was staring at him.

“Are you made of only fire?” They asked. Grillby nodded. “So, does that mean water hurts you?” Grillby didn’t answer, just stared at them. While he remained collected on the outside, on the inside he was panicking. If this child had any inkling to want to cause harm, it could mean the extinction of them all.

 

_ “You promised me their soul.”  _ Gaster stared incredulously at the king.  _ “They’re weak, soul ripe for the taking, and you’re healing them? Giving them food?” _

“Gaster they’re only a child. You expect me to kill a child, and one so similar to Asriel in age?”

_ “Yes.”  _ Gaster answered, his face expressionless.  _ “Yes, I do. They aren’t just a child. They belong to a race of murderers. Besides, just one soul and the synthetic replication can begin. If we don’t take their soul now, we’ll only be putting off the inevitable.”  _

“You will not lay a hand on them, Gaster.” Asgore told him, standing tall, towering over the skeleton. “Chara will be granted the same protections of a royal, and taking the life of a royal is treason. Which you know.” Gaster took a step back, hands shaking. “They are only a child.”

_ “I’ve seen what a child can do. I saw it first hand the night you and Toriel took me in.”  _

Asgore’s body tensed. He could no longer meet Gaster’s eyes. 

“I’m sorry Gaster… They were my friends, just as they were your parents. I understand. But Chara is different, I promise.”

Gaster glared at Asgore. “You could never understand.” He told the king, for once glad for the wince his voice caused.

Gaster walked into the bedroom, grabbed Grillby, and walked out, teleporting the two monsters to their home in Snowdin.

“Gaster?” Grillby asked. “Wingdings Gaster, are you okay?” Gaster held his skull in his hands. The cracks beneath his fingers were just as predominant as they’d always been. He resisted the urge to scream, frustrated beyond belief with the king of monsters. He felt two hands on his shoulders; two warm, strong, kind hands. The tension left Gaster’s body, and he turned around, burying his face in Grillby’s chest.

“I just hope they don’t hurt Asriel.” He whispered into the flames. “Anyone but Asriel.”

Grillby rubbed Gaster’s back. “We’ll make it through this. You’ll see.”


	3. * FIGHT

**Summary for the Chapter:**

> Challenger approaches: Chara

**Notes for the Chapter:**

> WARNING: Descriptions of attacks from the game ahead!

There was now an elevator. And Gaster hated it. The king had started its construction days after Chara had fallen. Just a short, three months later and it was fully functional. Gaster knew why he’d installed it. If Chara went missing, his lab would be the first place they’d look. Chara was another thing Gaster hated. He despised the human, and was often sickened by their love for dangerous pranks. Worse yet, Chara had confessed while Asriel was out of the room that they enjoyed hurting people. But they hadn’t said people, no. Chara had called other humans _things._ Their own species was nothing but things to them. After that, Gaster told Toriel he and Grillby were far too busy to be baby-sitting the two children anymore.

To add to Gaster’s discomfort were the rumors. Monsters had started to show up at shops with four HP or less. They’d say they were clumsy, that they’d fallen into some lava or something. But they looked afraid. Startled. The rumors were that Chara attacked the monsters until they were low on health, and then chose Mercy at the last second. It was sadistic.

Gaster heard the elevator doors open, and the scientist sighed. He got to attention, smoothing out his lab coat. He turned, expecting to see Asgore there, wanting some kind of progress on his work. When Gaster turned, he stumbled back a few steps.

Chara. With their red eyes, their permanent smile. With a knife in their hand.

“Hello Uncle Gaster.” They said, a little too sweetly for Gaster’s taste.

_“Where is Asriel?”_

“He's in his lessons with dad.” Chara was still smiling. “And I’m really bored. Will you play with me?”

 _“I don’t think I want to play the same games that you do.”_ Gaster signed.

“I don’t think you get a choice.” All around him, Gaster watched the world become monochromatic. The ghost-outline of his soul was visible, showing a simple purple heart. The human’s soul was also displayed, the upside down heart glowing a faint white. Gaster swallowed hard.

 _“I’m not going to fight you.”_ He signed. _“Please, walk away.”_

Chara laughed and swung their knife. Gaster stepped to the side, the slice missing completely. Since they’d walked into his lab, Chara’s smile finally disappeared. “What! How’d you do that!”

 _“Did you think I was going to stand there and take it?”_ Gaster asked, looking incredulous. Once again, he chose Mercy, and once again he sidestepped Chara’s slice.

“You can’t keep dodging forever!”Chara shouted.

Gaster chose Mercy. _“I don’t have to. Eventually Asriel will come looking for you down here, and you will stop.”_

Chara sliced at Gaster, and the skeleton ducked underneath the cut. “I don’t care if that cry baby is here or not! I’ll land a hit, you’ll see!”

Gaster felt his temper rise, but quickly buried it. In respect of the king, he would not hurt the child. _“Prince Asriel is not a cry baby.”_ Gaster signed instead.

“He is too! He whines and snivels at everything!” Chara yelled, and Gaster’s cheeks became a deep violet out of frustration. All the same, Gaster chose Mercy.

Chara sliced and sliced, hitting only air for the longest time.

Gaster was wavering, started to get exhausted. He wished the human would give up, but they didn’t. They kept going.

Until finally, Chara struck a blow.

Gaster felt his HP drop to just below half with the one cut, and he fell to his knees. He wondered if the human would try to finish him off, leaving his husband a widow. No. That was not going to happen.

Gaster got to his feet. His eyes disappeared, becoming two gaping holes, a smile cracking across his skull. He faced Chara, before he glanced at his options.

 

* FIGHT  
* MERCY 

 

W.D. Gaster chose * FIGHT.

 

Chara watched as bones began to fly at them at an alarming rate, some of them blue, some of them not. Chara couldn’t avoid them fast enough. Their HP dropped quickly, but the bones did stop. They went in for another slice at the skeleton, but their attack was dodged.

He chose * FIGHT once again, but this time Chara felt a tug on their soul. When they looked down, their soul was blue. With simple nods of his head, Gaster threw Chara’s soul left and right, making them crash hard into walls. Chara tried to fight against it, but barely could. When he threw Chara to the floor once again, bones were there, decreasing Chara’s HP until it was at 1.

“I HOPE YOU HAVE LEARNED SOMETHING TODAY, HUMAN.” Chara grimaced at the sound of his voice, and wondered if their ears would start to bleed. It was nails scratching on a chalkboard mixed with glass shattering mixed with television static. They couldn’t handle it. No more. They tried to hit Mercy, to get out of the fight, but the button had been barred off by bones, placed there by the "good" doctor himself.

There was another option. Chara hadn’t noticed it before.

Chara could reach something called a SAVE file. They shook as they reached for it, and the world went black for a moment.

When Chara opened their eyes, they were standing in the doorway of Gaster’s lab. The scientist was working, sitting instead of standing as he’d been when Chara had originally walked in.

“Hello Uncle Gaster.” Chara said, not as confident as they had been before.

 _“The power you have, Chara Dreemuur, is one that allows you to make better choices in your life. Use it wisely.”_ Chara didn’t reply. They turned around and left without another word.

 


	4. The Part Where There Is a Cliffhanger

**Summary for the Chapter:**

> Not gonna lie- This is mostly preference for what the next short is going to be about.

Gaster stopped on the doorstep to his and Grillby’s home. He needed a moment to collect himself once again. He could still feel it, being so lost and fighting so hard. He didn’t regret a moment of that fight. Not a single moment of a fight that didn’t happen.

Gaster sighed and ran his hands over his skull. Monsters weren’t supposed to remember Resets. Why he had was a mystery, and one that he’d explore in his lab first thing the next day. With hesitance, Gaster stepped into his house. Grillby was right where he usually was. Sitting on the couch, waiting. Gaster smiled and took off his coat. He hung it up, walked over to Grillby, and collapsed next to him on the couch. Grillby looked at him, and chuckled softly.

“Long day?”

“Oh you wouldn’t believe it. I had a visitor today. One Chara Dreemuur.” Gaster muttered bitterly.

Grillby wrapped an arm around his shoulders, pulling the scientist close to his chest. “Oh yeah? And how’d you handle it?”

“Pretty good.” Gaster nuzzled closer, wrapping his body around Grillby’s. He snuggled into the warm, orange flames, that were slowly becoming gold. “Children are awful, Grillby. Let’s never have any.” Although his words were meant as a joke, Grillby fell quiet. The gold flames turned back to orange, and he started to gently rub Gaster’s back. “Grillby, my dear, what’s wrong?”

“Nothing… I…” He sighed, and Gaster tilted his head up.

“What’s going on?”

Grillby hesitated, blue flames under his eyes as he tried to find the words for what he wanted to ask.

“Gaster, I want to have a child with you.”


End file.
